No Video after changed os

i used to have vista on a computer from scratch and it worked fine but i did'nt like it so i put xp media center on it and installed it into c/temp instead of c/windows to avoid losing data and it worked. then i tried installing in c/windows twice but because it gave me errors. then again i tried in c/temp and got it working. after i turned it off i turned it on a few hours later and it had no image and i manged to log in and it sounds an everything. my motherboard has no out output neither the two vga on my video card. i think it might be the driver but i'm not sure. i hope its not the motherboard.